You can play different scales. I like these two:
– A-Minor pentatonic [A-C-D-E-G]

Another good way is, when you change the pentatonic-scales with the chords. So you play
– A-Minor pentatonic [A-C-D-E-G] over Am
– D-Minor pentatonic over Dm [D-F-G-A-C] and
– E-“altered” pentatonic [E-G-G#-C-D] over E7
That sounds complicated, but it´s not, because you always just need to change one note from you Am-Pentatonic. Over Dm you Change the E to F, and over E7 you change the A to G#.

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